Telephonic apparatus.



E. A. GRAHAM.

TELEPHONIC APPARATUS.

APPLICATION FILED mm. 1, 19 1.

Patented De0. 17, 1912.

2 SHBETSSHEET 1.

1a. A, GRAHAM; TELBPHONIO APPARATUS.

APPLICATION FILED DEO. 1, 1911.

1,047,788. Patented Dec. 17,1912.

2 sums-61mm z.

EDWARD ALFRED GRAHAM, OF BROCKLEY; LONDON, ENGLAND.

TELEPHONIC APPARATUS.

Specification of Letters Patent.

Application filed Eecember 1. 1911. Serial No. 663,235.

Patented 1700.1731'1912.

Be it known that I, Eowann Amman Gnlununa subject of the King" otf (treat Britain and Ireland. residing at Iil'(i(lilt in the county of London. England. have invented Improvements in or Relating to 'Telephonic AII'paratUs, of which the following is a specification.

Hitherto it has been common to provide a telephonic instrument with a sound amplifying trumpet for use in quiet situations. and another type of instrument. provided with side hearing tubes, for use in noisy stations, such as in the engine rooms of a tance away from the instrument when com-- parative quiet reigns 1n the vicinity thereof,

ship, machinery spaces, gun turrets and the like.

Many situations, particularly on board ship, may houeverbe generally tree from noise while at times there may be considerable no se occasioned as by machinery for training gun turrets, the working of capstans and so forth, and in these positions the provision of a telephonic instrumentby which instructions can be received without the necessity of placing the receiver or receivers to the car or ,cars in the ordinary course, and may yet be rendered audible even when there is considerable noise, would be advantageous. i

The present invention h as for its object to provide improved telephonic apparatus specially suitable for use in situations which are at times comparatively quiet and in which at other times there is considerable extraneous noise. ceiving portipn of telephonic apparatus according to this invention comprises a telephonic receiving device, a sound amplifying trumpet whereby the sounds reproduced by the telephonic receiver when suitably constructed, can be heard at-a considerable d sand one or more hearing tubes adapted to be placed to the ear or ears in orderto hear reproduced sounds distinctly when theexs' traneous nolse is such as would otherwise" prevent these sounds being heard. Such telephonic receiving apparatuscan' be used in conjunction with a telephonic transmitter, and other device or devices usually associated with telephonic apparatus, andcan be directly combined therewith as one structure or not, as may be found" convenient or desirable. y I

In the accompanying illustrative draw- For this purpose, the re casing l which is provided with a suppjorh ing Socket 1 contains a telephonic receiver preferably such as is described in the specification of my British Letters Patent No. 25112 of 1909 and comprising a permanent magnet a to one pole .of which is fixed a polar extension a carrying the receiver coil a and to the other pole of which is pivoted a lever a one end ofwh-ich terminates near to and opposite the polar extension and the other end of which is fixed to the receiver diaphragm a so as to impart an initial mechanical stress thereto. The casing2 has formed at its rear side a sound passage?) communicating with the diaphragm cham-- ber 11, of the receiver and having three branches, viz: a middle vertical branch or passage 3 and two side branches 3 and 3,-

the middle branch 3 passing to a stationary sound amplifying trumpet 3 and the side branches 3, 3 communicating respectively with pendent sidesound tubes 3*,3which are connected to'the casing 2 by knuckle or universal joints 3 The sound tubes 3 and 3" are provided with elastic ear pads 3.. As will beseen, the arrangement is such as will atlow of the telephonic 'sounds being' received by the trumpet 3 or by the sound tubes 3*, 3, as maybe desired. The upper casing 1 also contains a'shunt resistance4 of a nonrinductiv'e or substantially non-inductive' character, a set of contacts 5 'foruse'in' calling a distant station, a signal lamp 6, a

relay 7 forclosing the circuit of the lamp, a

calling vibrator 8 and a set of terminals 9, 9!, 9, 9 serving to connect the line wires which enter the casing 1 through a gland 10. The forward portion of the casing 1 carries the calling push 11, and, a lens 12 for the signal lamp 6. Thespindle 13' of the push 11 passes through a spring chamber 14 screwed against a packing ring 15 andfinto i a. boss 16, and'is provided with an insulating top 17. The lens 12 is mountedin asocket 18 screwedinto a boss. 19 against a packing ring 20. 'The lower easing 2 contains, attached to the front cover 21, a transmitter at 22, of the granular type, having a front carbon diaphragm mounted in known manner behind the mouth piece 22 and having a rear electrode of carbon mounted so as to be intermittently revolved by means of ratchet gear 24 in a knqwn manner.

25 is the lever which operates the switch member 26 connected to the ratchet mechanism 24 and carrying the movable contact pins 26* for engagement with the pairs of stationary switch contacts 26 and 26 for closing the electrical circuits of the apparatus. The said lever 25 is arranged to be operated through a spindle 25 from a thumb lever 27 external to the casing 2 and is also provided with a roller 28 arranged to be operated by a finger or projection 29 on a slide bar 30, which is arranged to be moved by a crank pin 31 connected to the right hand knuckle 3 of the side sound tube 3. Thus,

the switch member 26 will be moved to ac struments constructed as hereinbefore described with reference to Figsfil to 4 are connected together and to positive and negative supply mains 41 and &2 respectively supplied with current from a dynamo 43 is an inductive line coil, 2'. e. a choking coil, ar-

anged in circuit with the supply main 41 forthe purpose of steadying the generated currents, preventing the reproduction in the telephone circuit of disturbances in any part of the circuit, and of preventing cross talking as between different pairs of telephonic instruments that may be engaged at the same tlme, all as well understood.

As will be seen from the diagram, each resistance t is arranged to be temporarily con nected by the switch 26, 26, 26, 26* in parallel with the circuit, or portion of the circuit, which includes the transmitter 22 of one instrument with the receiver coil a of the other instrument in such manner that the inductance, due to the line coil 43, is excluded from the said circuit or portion of the circuit, as described in the specification of my British Letters Patent No. 3935 of 1907. When the instruments are connected in pairs to say a 51K cell electric battery instead of to a dynamo or the like and the line coil .43 omitted, the shunt resistances 4 are disconnected,

As will be obvious other known or suitable types of loud speaking transmitters and re ceivers may be used in lieu of the forms hereinbefore particularly referred to, with.- out departing from the essential features of the invention.

\Vhat I claim is 1.. In a loud speaking telephonic instrument, a casingcomprising a circular receiver compartment with its axis arranged vertically, a hinged lid closing said compartment and a series of peripheral bosses adapted respectively to accommodate a switch push,

a signal lamp and a gland for electric conductor s.

2. In a loud speaking telephonic instrument, a casing comprising a circular re ceiver diaphragm compartment with its axis arranged vertically and having an axially disposed opening in the bottom, a hinged lid for the receiver compartment an a series of peripheral bosses adapted respec tively to accommodate'a switch push, a sig I nal lamp and glands for electric conductors,

lid for the receiver compartment and a series of peripheral bosses adapted respectively to V accommodate a switch push, a signal lamp and a gland for electric conductors, a rigid body part adapted to'he connected to the receiver compartment and formed respertively with transmitter compartment, a passage adapted to connect a stationary trumpet to the receiver compartment through the opening in the bottom aforesaich branch passages terminating in hollow bosses. a pair of hearing tubes and universal joints connecting said tubes to the hollow bosses.

4. In a loud speaking telephonic instrument, a casing comprising a cylindrical receiver diaphragm compartment with its axis arranged vertically and having an axially disposed opening inthe bottom a supporting socket to one side of said opening a hinged lid and a series of peripheral bosses adapted respectively to accommodate a switch push, a signal lamp and a gland for electric conductors.

vertically andfhaving an axially disposed adapted respectively to aceonnnodate a opening in the bottom, a supporting socket to one side of said opening, a hinged lid and a series of peripheral bosses adapted respectively to accommodate a switch push, a signal lamp and glands for electric eonductors, a'body part adapted to be connected to the receiver compartment and formed respectively with a rectangular transmitter compartment, a passage adapted to connect a stationary trumpet to the receiver compartluent through the opening in the bottom aforesaid and branch passages terminating in hollow bosses adapted to receive movable hearing tubes. 6. A loud speaking telephonic instrument. comprising a circular receiver d aphragm compartment with its axis arranged vertically and having anaxially disposed opening in the bottom, a hinged lid for said compartment and a series of peripheral bosses switch push, a signal lamp and a gland for electric conductors, a body part adapted to be connected to the receiver compartment and formed respectively with a transmitting compartment, a passage adapted to con ncct a stationary trumpet to the receiver compartment through the opening in the bottom aforesaid and bran h passages in c'omnumieation with the lirst mentioned passage and receiver t-ompartinent and termi Dating in hollow bosses adapted to receive movable hearing tubes.

7. A loud speaking telephonic instrument comprising a circular receiver" diaphragm compartment with its axis arranged vertically and having an axially disposed opening in the bottom, a hinged lid for said compartment and a series of peripheral. bosses adapted respectively to aeeouu'nmlate a switch push, a signal lamp and glands for electric conductors, a body part adapted to be connected to the receiver compartment and formed respectively with a rectangular transmitting compartment, a passage adapted to connect a stationary trumpet to the receiver compartment through the opening in the bottom aforesaid, branch passages in communication with the first mentioned passage and terminating in hollow bosses, a

pair of hearing tubes and universal joints.

a stationary trumpet to the receiver compartment through the-opening in the bottom aforesaid and branch passages in communication with the first mentioned passage and terminating in hollow bosses adapted to receive movable hearing tubes.

t). A loud speaking telephonic instrument comprising a circular receiver diaphragm t -oinpartment with its axis arranged vertically and having an axially disposed opening in the bottom and a supporting socket to one side of said opening, a hinged lid for said t'ompat'tlllellt and a series of peripheral bosses adapted. respectively to accommodate a switch push, a signal lamp and a gland for electric conductors, a body part adapted to be connected to the receiver compartment and formed respectively with a rectangular transmitting con'ipartment, a passage adapted to connect a stationary t'rumpetto the receiver compartment through the opening in the bottom aforesaid, branch passages in counnunication with the first mentioned passages and terminating in hollow bosses, a pair of hearing tubes and universal joints connecting the hearing tubes to the branches aforesaid.

Signed at- St; Andrews Works, Crofton Park London this third day of November EDW A RI ALFRED GRAHAM. \Vit nesses:

.llowAnn llllttl'lNE BARNARD, Hnnnr d VILIJAM Dirnosn. 

